A. The provisions of this Chapter governing size and weight do not apply
to:

1.

Any vehicle, combination of vehicles, article, machine, or other
equipment in use by the Federal Government, the State of Oregon, or any county
or city while in the immediate vicinity of and involved with the construction,
maintenance, or repair of public highways;

2. Any vehicle in use by a mass transit district for the purposes
authorized under ORS 267.010 to ORS 267.390, provided the size or weight of
the vehicle is approved by the City for that route; or

3. Any vehicle, combination of vehicles, article, machine, or other
equipment operated under a permit issued by the Traffic Engineer and in
compliance with the conditions and restrictions thereof.

B. None of the size limits described in ORS 818, except the maximum
limit of allowable extension beyond the last axle of a combination of vehicles,
apply to agricultural equipment hauled, towed, or moved upon any street if the
movement is incidental to the farming operations of the owner of the
agricultural equipment.